1. Field of the Invention
The present invention relates to medical devices and procedures for applying localized heat to a site in the patient""s body, particularly for purposes such as sterilization of a female patient by closing of the fallopian tubes.
2. Description of the Prior Art
The prior art includes devices and procedures for applying localized heat to a site in a patient""s body for a number of purposes, generally including altering, removing or destroying tissue in a patient""s body.
U.S. Pat. Nos. 4,773,413 and 4,662,368 both to Hussein et al. disclose a localized heat applying medical device powered by laser energy transmitted through an elongated conduit. The heat applying device includes a bulbous heat generating element, having an aperture in the forward end of the device permitting a portion of the laser energy to be transmitted out the aperture and directly applied to the patient""s body tissue. The devices disclosed in Hussein et al. are particularly designed for use in treating cardiovascular disease by removing arteriosclerotic deposits from blood vessels. Commercial embodiments of the Hussein et al. device are marketed by LaserControl Medical Systems Division of Trimedyne, Inc., of Santa Ana, Calif. One such commercially available device is marketed as the Spectraprobe(trademark)-80, which is designed such that approximately eighty percent of the laser energy transmitted thereto is emitted through the optical aperture at the end of the device. The Spectraprobe(trademark)-80 has a tip diameter of about 2.5 millimeters.
German Patent No. 2,826,383, published Dec. 20, 1979, of Eichler et al., discloses a laser probe placed directly against or inserted into the patient""s tissue for treating the same.
It is also known to use laser powered devices in hysteroscopic procedures. For example, a surgical procedure referred to as an xe2x80x9cendometrial ablationxe2x80x9d has been recently developed as an, alternative to hysterectomy for treatment of excessive uterine bleeding. In this procedure, an Nd:YAG laser is used to destroy the entire endometrium lining the uterus. An optical fiber is inserted in the uterus by means of a hysteroscope to conduct the laser energy to the endometrium. With the aid of a parallel optical viewing fiber of the hysteroscope, the end of the laser transmitting fiber is slowly moved across the surface of the endometrium so that the laser energy penetrates and destroys the endometrium which is on the order of three millimeters thick. Typical prior art procedures have utilized a bare optical fiber for transmitting the laser energy. Two techniques have been developed. By one technique, the end of the bare optic fiber is actually touched to the endometrium in a xe2x80x9cdraggingxe2x80x9d procedure. By a second technique, generally referred to as xe2x80x9cblanchingxe2x80x9d, the bare tip of the optic fiber is held several millimeters away from the endometrium. These techniques are generally described in Daniell et al., xe2x80x9cPhotodynamic Ablation Of The Endometrium With The ND:YAG Laser Hysteroscopically As A Treatment Of Menorrhagiaxe2x80x9d, Colposcopy and Gynecologic Laser Surgery, Volume 2, No. 1, 1986; Mackety, xe2x80x9cAlternative To Hysterectomy: Endometrial Ablation By Laser Photovaporizationxe2x80x9d, Today""s OR Nurse, Volume 8, No. 4; and Goldrath et al., xe2x80x9cLaser Photovaporization Of Endometrium For The Treatment Of Menorrhagiaxe2x80x9d, AM. J. Obstet. Gynecol., Volume 140, No. 1, page 14, May 1, 1981.
The Goldrath et al. and Daniell et al. articles cited above, both suggest that patients undergoing an endometrial ablation procedure will probably be sterile following the procedure. The work of Goldrath et al. and Daniell et al. was not directed to the end purpose of sterilization, but it was observed as a side effect of the treatment. For reasons further described herein, it is believed that the cause of the sterility observed by Goldrath et al. and Daniell et al. was the destruction of the patient""s endometrium.
A recent improvement upon the endometrial albation procedure, wherein a heat generating tip is attached to the end of the laser transmitting conduit, with the tip being designed to laterally emit a portion of the laser energy is disclosed in Everett et al. pending Application No. PCT/US89/02492 filed Jun. 7, 1989, which has been published as International Publication No. WO 89/11834 on Dec. 14, 1989. That application is a continuation-in-part of U.S. patent application Ser. No. 205,218 filed Jun. 10, 1988.
In all of the endometrial ablation procedures set forth in the references discussed above, the treatment is directed to the endometrium, that is the lining of the uterine cavity, for the purpose of destroying that lining to prevent excessive bleeding. The procedures are not directed to the purpose of closing the fallopian tubes to induce sterilization. Furthermore, the endometrial ablation procedures do not involve any substantial fixed contact of the tip of the laser fiber, or of a heating device on the end of the laser fiber, with the tissue, but rather involve a continuous movement of the tip while dragging it across, or moving it while held a slight distance away from, the tissue.
The present invention provides procedures for sterilizing patients by the use of heat and laser light energy applied by holding a heating device in fixed contact with tissue adjacent the tubal ostia in order to coagulate the interstitial portion of the fallopian tubes thereby closing the fallopian tubes. Localized heat applying devices are provided which are particularly adapted for use in such procedures.
A localized heat applying medical device for applying heat to tissue adjacent a patient""s tubal ostia in order to close the patient""s fallopian tubes and sterilize the patient includes an elongated light transmitting conduit having a proximal end and a distal end. A bulbous heat generating means is mounted on the distal end of the conduit for converting light energy transmitted by the conduit in part to heat thereby raising the temperature thereof. The bulbous heat generating means has a larger portion with an outside diameter of at least about two millimeters, and has a tapered forward portion with a forwardmost tip having an outside diameter no greater than about one millimeter, so that the tip can be received through one of the tubal ostia with the larger portion of the bulbous heat generating means engaging an inner wall of the patient""s uterus adjacent said one of the tubal is ostia. The bulbous heat generating means includes a light transmitting aperture means extending through the tapered-forward portion to the tip for enabling light energy transmitted by the conduit in part to pass through the aperture means into the fallopian tube associated with said one of the tubal ostia.
Procedures utilizing such a device include steps of inserting into the patient""s uterus the elongated laser light energy transmitting conduit having the heat generating device on the distal end thereof. Then the heat generating device is maintained in fixed contact with the inner wall of the patient""s uterus adjacent the tubal ostia for a sufficient time and while transmitting sufficient energy to the heat generating device to coagulate a substantial part of the interstitial portion of the patient""s fallopian tubes to close the same.
Numerous objects, features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the following disclosure when taken in conjunction with the accompanying drawings.